Object localization in X-ray images

Abstract

An x-ray system (100) comprises a gantry (102) on which an x-ray source (104) and an x-ray detector (106) are mounted. A control unit (110) comprises means (114) for effectuating a wiggling motion of the gantry, wherein an axis (116) connecting the x-ray source and the x-ray detector traces a surface (128) of a cone (118). The x-ray source and the x-ray detector have a fixed position with respect to the axis. The control unit comprises means (120) for acquiring a series of x-ray images during the wiggling motion of the gantry. An object recognition unit (122) detects an object (124) appearing in the series of x-ray images to obtain a tracked path. A depth estimation unit (126) uses the tracked path for estimating a depth parameter indicative of a position of the object in a direction substantially parallel to the axis (116).

Description

FIELD OF THE INVENTION[0001]The invention relates to object localization in x-ray images.BACKGROUND OF THE INVENTION[0002]X-ray fluoroscopy is often used for guiding electrophysiology (EP) ablation procedures. It shows the position of all catheters in real-time. 3D mapping has greatly helped the development of complex ablation procedures by showing the position of the catheter in relation to a 3D representation of the cardiac contours. However, neither tool can show the position of all catheters in relation to each other or the detailed endocardial anatomy, in real time.[0003]The EP Navigator, which is available from Philips Healthcare, is able to confirm the position of a catheter or lead position with respect to a 2D projection of a detailed 3D cardiac anatomy in the EP intervention lab. This information can help a physician to carry out complex EP procedures with greater confidence, in a more intuitive way. Such tools may provide an automatically segmented 3D CT image. This image...

AI Technical Summary

Benefits of technology

This patent describes a method for getting a depth estimate of an object during a medical intervention without using special hardware. The method involves using the existing x-ray system already in use during the intervention. The x-ray images provide information about the object's position in two dimensions, but not in the third dimension (depth). The movement of the x-ray source and detector creates views from different perspectives, which can be used to estimate the depth of the object. The method is convenient to use, as it doesn't involve large rotational movements or time-consuming positioning procedures. It also improves the accuracy of the depth estimate compared to stereo computations based on only two images. The wiggling motion of the x-ray system is limited in its motion and can be repeated a number of times to improve accuracy.

Problems solved by technology

However, neither tool can show the position of all catheters in relation to each other or the detailed endocardial anatomy, in real time.

Due to the complexity of the anatomy and the lack of integrated tools, complex ablation procedures are very time-consuming and usually last several hours.

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